CDO was installed by downloading the Win32 zip from this link…

Extract the two files to the folder you want to use for conversions.

Test that CDO is working by opening a command prompt. Move to the folder containing 'cdo.exe' and type 'cdo.exe'. If it is working you will see some help information.

Optional:To make using CDO more flexible you can add the location of 'cdo.exe' and the '.dll' to the path environment variable on your computer.

To convert netcdf (.nc) files to grib it is helpful to make a command script in the directory where you have your '.nc' files:

\\
# change name of uo variable\\\\
cdo chname,uo,var49 is.nc is1.nc\\\\
# change name of vo variable\\\\
cdo chname,vo,var50 is1.nc is2.nc\\\\
# convert the netCDF file to grib1\\\\
cdo -f grb copy is2.nc is.grb\\

Change the initial file name ('is.nc') to the name of your .nc file and run the script:

The commands an also be run individually.

Open the grib file with OpenCPN in the normal way.